PostgreSQL的initdb 源代码分析之六

继续分析

下面的是获取运行此程序的用户名称，主要还是为了防止在linux下用root来运行的情形。

    effective_user = get_id();
    if (strlen(username) == 0)
        username = effective_user;

接下来，是准备好一写预备生成的文件的名称变量：

    set_input(&bki_file, "postgres.bki");
    set_input(&desc_file, "postgres.description");
    set_input(&shdesc_file, "postgres.shdescription");
    set_input(&hba_file, "pg_hba.conf.sample");
    set_input(&ident_file, "pg_ident.conf.sample");
    set_input(&conf_file, "postgresql.conf.sample");
    set_input(&conversion_file, "conversion_create.sql");
    set_input(&dictionary_file, "snowball_create.sql");
    set_input(&info_schema_file, "information_schema.sql");
    set_input(&features_file, "sql_features.txt");
    set_input(&system_views_file, "system_views.sql");

接下来，这个函数很有趣，是为了information_schema的版本信息的：

    set_info_version();

展开后可以看到：

调试其代码，可以得到  infoversion 的信息是：09.01.0002

/*
 * extract the strange version of version required for information schema
 * (09.08.0007abc)
 */
static void
set_info_version(void)
{
    char       *letterversion;
    long        major = 0,
                minor = 0,
                micro = 0;
    char       *endptr;
    char       *vstr = xstrdup(PG_VERSION);
    char       *ptr;

    ptr = vstr + (strlen(vstr) - 1);
    while (ptr != vstr && (*ptr < '0' || *ptr > '9'))
        ptr--;
    letterversion = ptr + 1;
    major = strtol(vstr, &endptr, 10);
    if (*endptr)
        minor = strtol(endptr + 1, &endptr, 10);
    if (*endptr)
        micro = strtol(endptr + 1, &endptr, 10);
    snprintf(infoversion, sizeof(infoversion), "%02ld.%02ld.%04ld%s",
             major, minor, micro, letterversion);

}

接下来，看这个，因为没设置debug状态之类的，所以可以跳过：

    if (show_setting || debug)
    {
        fprintf(stderr,
                "VERSION=%s
"
                "PGDATA=%s
share_path=%s
PGPATH=%s
"
                "POSTGRES_SUPERUSERNAME=%s
POSTGRES_BKI=%s
"
                "POSTGRES_DESCR=%s
POSTGRES_SHDESCR=%s
"
                "POSTGRESQL_CONF_SAMPLE=%s
"
                "PG_HBA_SAMPLE=%s
PG_IDENT_SAMPLE=%s
",
                PG_VERSION,
                pg_data, share_path, bin_path,
                username, bki_file,
                desc_file, shdesc_file,
                conf_file,
                hba_file, ident_file);
        if (show_setting)
            exit(0);
    }

再往下看：

    check_input(bki_file);
    check_input(desc_file);
    check_input(shdesc_file);
    check_input(hba_file);
    check_input(ident_file);
    check_input(conf_file);
    check_input(conversion_file);
    check_input(dictionary_file);
    check_input(info_schema_file);
    check_input(features_file);
    check_input(system_views_file);

check_input，在这里是检查文件是否存在。

其实，postgres.bki等文件，都位于 src/backend/catalog目录下......

接下来：

    setlocales();

展开后看：发现得到的 locale 变量是个空值。

/*
 * set up the locale variables
 *
 * assumes we have called setlocale(LC_ALL,"")
 */
static void
setlocales(void)
{
    /* set empty lc_* values to locale config if set */

    if (strlen(locale) > 0)
    {
        if (strlen(lc_ctype) == 0)
            lc_ctype = locale;
        if (strlen(lc_collate) == 0)
            lc_collate = locale;
        if (strlen(lc_numeric) == 0)
            lc_numeric = locale;
        if (strlen(lc_time) == 0)
            lc_time = locale;
        if (strlen(lc_monetary) == 0)
            lc_monetary = locale;
        if (strlen(lc_messages) == 0)
            lc_messages = locale;
    }

    /*
     * override absent/invalid config settings from initdb's locale settings
     */

    if (strlen(lc_ctype) == 0 || !check_locale_name(lc_ctype))
        lc_ctype = xstrdup(setlocale(LC_CTYPE, NULL));
    if (strlen(lc_collate) == 0 || !check_locale_name(lc_collate))
        lc_collate = xstrdup(setlocale(LC_COLLATE, NULL));
    if (strlen(lc_numeric) == 0 || !check_locale_name(lc_numeric))
        lc_numeric = xstrdup(setlocale(LC_NUMERIC, NULL));
    if (strlen(lc_time) == 0 || !check_locale_name(lc_time))
        lc_time = xstrdup(setlocale(LC_TIME, NULL));
    if (strlen(lc_monetary) == 0 || !check_locale_name(lc_monetary))
        lc_monetary = xstrdup(setlocale(LC_MONETARY, NULL));
    if (strlen(lc_messages) == 0 || !check_locale_name(lc_messages))
#if defined(LC_MESSAGES) && !defined(WIN32)
    {
        /* when available get the current locale setting */
        lc_messages = xstrdup(setlocale(LC_MESSAGES, NULL));
    }
#else
    {
        /* when not available, get the CTYPE setting */
        lc_messages = xstrdup(setlocale(LC_CTYPE, NULL));
    }
#endif}